#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>
#include<math.h>

double SQ(double n, int x)
{
    if (x == 1)
        return n;
    else
        return n + SQ(sqrt(n), x - 1);
}

int main() {
    int  x;
    double n;
    while (scanf("%lf %d", &n, &x) != EOF)
    {
        double ret = SQ(n, x);
        printf("%.2f\n", ret);
    }
    return 0;
}